“Flour is derived from a grain that comes directly from the field and typically is not treated to kill bacteria,” says Leslie Smoot, Ph.D., a senior advisor in FDA’s Office of Food Safety and a specialist in the microbiological safety of processed foods. So if an animal heeds the call of nature in the field, bacteria from the animal waste could contaminate the grain, which is then harvested and milled into flour.

Common “kill steps” applied during food preparation and/or processing (so-called because they kill bacteria that cause infections) include boiling, baking, roasting, microwaving, and frying. But with raw dough, no kill step has been used.

And don’t make homemade cookie dough ice cream either. If that’s your favorite flavor, buy commercially made products. Manufacturers should use ingredients that include treated flour and pasteurized eggs.